Usage and precautions of feed grade Clostridium butyricum in aquaculture

      Feed grade Clostridium butyricum should be used in aquaculture based on its biological characteristics (such as good resistance to stomach acid and high temperature, but sensitive to strong oxidants) and the feeding habits of aquatic animals. Scientific usage methods should be adopted, and potential risks should be avoided. The specific measures are as follows:

1、 Usage method

1. Feed addition (core method)

      Direct mixing: Mix the Clostridium butyricum preparation (powder or granule) directly with aquatic feed (compound feed, expanded feed, pellet feed, etc.) at the recommended dosage, ensuring that each feed is coated with the bacterial agent. Suitable for all aquatic animals, especially fish that feed on compound feed (such as grass carp, tilapia), shrimp, crabs, etc.

      Dosage: Adjust according to the animal species and growth stage. It is generally recommended to add 100-500 grams per ton of feed (the number of live bacteria is usually 10 ⁸ -10 ⁹ CFU/g). For example:

      Juvenile (such as shrimp fry, fish fry): Add 300-500 grams per ton of feed to strengthen intestinal colonization;

      Adults (such as adult fish and shrimp): Add 100-300 grams per ton of feed to maintain intestinal health.

      Addition before granulation: If the feed needs to be subjected to high-temperature granulation (80-90 ℃), Clostridium butyricum can be mixed with the feed raw materials before granulation to utilize its high-temperature resistance (some strains can tolerate short-term high temperatures below 90 ℃) and reduce losses.

2. Water splashing (auxiliary method)

      Applicable scenarios: during the seedling stage (such as shrimp pond, fish pond), when there are significant fluctuations in water quality during the later stages of aquaculture, or when animals have weak feeding abilities (such as juveniles and post disease recovery stage).

      Operation method: Dilute the preparation of Clostridium butyricum with water and sprinkle it evenly throughout the pool, indirectly affecting aquatic animals by improving the water's microecology (such as inhibiting harmful bacteria such as Vibrio in the water and reducing the risk of intestinal infection).

      Spraying dose: 50-100 grams per acre of water surface (1 meter deep), once every 7-10 days, adjusted according to water quality.

3. Coordination of feeding methods

      Juvenile opening stage: Clostridium butyricum can be mixed with soybean milk, algae and other opening bait and fed to promote early colonization of intestinal flora of larvae.

      Drug bait synergy: After the use of antibiotics in aquatic animals, feed feed containing Clostridium butyricum every 24-48 hours to help restore intestinal microbiota balance (avoiding direct killing of Clostridium butyricum by antibiotics).

2、 Precautions

1. Compatibility with other substances

      Avoid mixing with strong oxidants: Clostridium butyricum is an anaerobic Gram positive bacterium that is sensitive to strong oxidants such as potassium permanganate and potassium hydrogen persulfate. The two should be used at least 48 hours apart (first disinfect the bottom, then replenish the bacteria).

      Interval with antibiotics: When using broad-spectrum antibiotics (such as florfenicol and enrofloxacin), feeding Clostridium butyricum should be temporarily suspended and resumed 2-3 days after discontinuation to prevent the killing of live bacteria.

      Synergy with other probiotics: It can be used in combination with lactic acid bacteria, Bacillus subtilis, etc. (such as Clostridium butyricum+Bacillus subtilis, the former colonizes the intestine and the latter improves water quality), but it is necessary to avoid excessive mixing with acid producing strains (which may affect the activity of Clostridium butyricum).

2. Storage and processing conditions

      Storage requirements: After sealing, place in a cool and dry place (temperature<25 ℃), avoid direct sunlight; Low temperature storage (around 4 ℃) can extend the shelf life (usually 12-18 months).

      Processing precautions: If the feed requires high-temperature granulation, it is recommended to control the granulation temperature below 85 ℃ (some high-temperature resistant strains can tolerate short-term treatment at 90 ℃), or choose the post spraying process (spraying the microbial agent on the surface of the feed after granulation) to reduce the loss of live bacteria.

3. Dose and usage cycle

      Avoid excessive addition: Overuse may lead to an imbalance in gut microbiota (such as excessive accumulation of butyric acid that stimulates the intestines), which can actually affect feeding. It should be strictly added according to the recommended dosage, and can be appropriately increased during the juvenile stage, but not exceeding twice the recommended amount.

      Continuous use: Clostridium butyricum needs to colonize in the intestine to form a dominant microbial community. It is recommended to use it continuously for 1-2 weeks and then switch to periodic addition (such as stopping for 1 week after 2 weeks of use) to maintain the effect in the long term.

4. Water quality and environmental adaptation

      Be cautious when water quality deteriorates: When the ammonia nitrogen and nitrite in the water body are too high (such as>0.5 mg/L) or the pH is less than 6.5, the water quality needs to be improved first (such as changing the water or using bottom modifiers), and then adding Clostridium butyricum, otherwise it is not conducive to its reproduction.

Adjustment for different breeding modes:

      Factory based high-density farming: increase the frequency of use (such as adding feed 2-3 times a week), strengthen intestinal health to cope with stress;

      Pond aquaculture: Combining water splashing to simultaneously improve the water and intestinal microbiota;

      Cage aquaculture: The focus is on adding feed to reduce the dilution of microbial agents by water flow.

5. Safety and Compliance

      Choose legitimate products: Use butyric acid clostridia preparations that comply with the "Catalogue of Feed Additive Varieties", check the manufacturer's veterinary drug GMP certification or feed additive production license, and avoid using inferior products (insufficient live bacteria or excessive miscellaneous bacteria).

      Avoid replacing basic management: Butyricibacter is an "auxiliary tool" and cannot replace basic aquaculture measures such as water quality control, rational feeding, and disease prevention and control. It needs to be coordinated with scientific management to maximize its effectiveness.

summarize

      Feed grade Clostridium butyricum is mainly added to feed and supplemented by water splashing in aquaculture, with the core of achieving dual improvement of gut and water microbiota through continuous supplementation of live bacteria. In practical applications, attention should be paid to compatibility, storage conditions, and dosage control, and flexible adjustments should be made based on the breeding objects and environment to maximize its growth promoting and disease fighting effects.